Bivalves are primary consumers that play an important ecological role and economical relevance due to their position in the aquatic food web and their commercial value as food source to human beings. During the last decades the interest in understanding the cellular mechanisms of organism-level responses to environmental changes strongly increased. Indeed, determining future boundaries and ranges that marine organisms will occupy associated to climate changes have heightened interest, as abiotic or physical factors are the primary reasons for these shifts. Temperature highly affects composition and biosynthesis of fatty acids. These changes may also have implications for enzymatic activity because a decrease in long-chain polyunsaturated fatty acid and / or increase in cholesterol can reduce enzyme efficiency. Thus, this study proposes to determine the biochemical effects of temperature in two marine mollusc bivalves – Scrobicularia plana and Cerastoderma edule, and compare the nutritive value of both bivalve species under exposure of a range of temperature.